U.S. Pat. No. 5,421,054 to Dawson, et al., commonly-owned with this application, illustrates examples of discs having flexible fins. The fins extend upward beyond the peripheries of the (generally planar portions of the) discs. As noted in the Dawson patent, these fins “assist [the disc] in maneuvering over many objects (such as drains, lights, valves, and nozzles) projecting from internal surfaces of pools.” See Dawson, col. 2, 11. 59-61. Because located at the peripheries of discs, the fins also “contact most protrusions before the remainder[s] of” the discs. See id., 1. 63.
Commonly-owned U.S. Pat. No. 5,465,443 to Rice, et al. discloses additional examples of discs having flexible fins. Pending U.S. patent application Ser. No. 11/708,925 of Moore, et al. describes yet additional sample discs with flexible fins. The finned portions of these discs typically form the forwardmost structure of their associated pool cleaners, so that they usually contact protrusions and other obstacles in advance of the remainders of the cleaners. Stated in the Moore application is that the fins “provid[e] sufficient rigidity to [the] disc to enable it to ride over various objects, including many drains, lights, valves, and other nozzles, projecting from internal surfaces of pools.” See Moore, p. 8, 11. 20-22.
In these and other discs having fins (or similar outwardly-extending protrusions), the fins and generally planar portions of the discs are usually integrally formed. The fins of the Dawson and Rice patents, for example, may be molded together with generally planar portions of the corresponding discs. Fins of the Moore application, likewise, may be molded together with the forward section of the disc.
Lacking, therefore, from these patents and application is any discussion of outwardly-extending protrusions that comprise multiple pieces. Similarly lacking is any discussion of adaptors for the fins to accommodate circumstances in which the coefficient of friction of, e.g., the leading edge of the disc needs to be decreased or when lateral bending of the fins needs to be discouraged. Also not specifically addressed is any mechanism for enhancing integrated movement of the fins and planar disc sections when desired.